Rail with rollers and process of manufacture

ABSTRACT

Roller rail comprising a lower profile whose section is one of, U-shaped or omega-shaped, a plurality of rollers, and an upper profile made of a steel band, cut and embossed, used as a roller carrier. The band comprises edges which are folded and crimped on upper rims of the lower profile, which edges are linked together by crossbeams between which the rollers are positioned. The process of manufacture of a roller rail comprises preparing by, one of, folding or profiling operations, a sheet metal band, a lower profile with one of, U-shaped or omega-shaped section, and an upper profile carrying a plurality of rollers and assembling the profiles together by folding and crimping the edges of the sheet metal band constituting the upper profile onto upper rims of the lower profile.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. § 119 of FrenchPatent Application No. 96 14838, filed Nov. 28, 1996.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a roller rail used in the field ofdynamic layer storage for preparing orders or supplying workstations.

2. Discussion of Background Information

These roller rails are often composed of a profile made of sheet metalwhose section is U-shaped or omega-shaped, open at the upper end andwhose rims are arranged in order to accommodate the axles of therollers, as described for example in U.S. Pat. No. 3,586,142.

Another type of rail, described in FR-A-2 563 506, comprises a sheetmetal profiled rail and a plastic material strip which separates andmaintains the rollers on the rail. This plastic strip also improves theresistance properties of the rail while preventing its opening to acertain extent when carrying heavy loads.

There are also rails using a U-shaped sheet metal profile, but opendownwardly. The bottom of the U has been drilled to accommodate therollers. This type of rail, described notably in U.S. Pat. No.4,186,830, also comprises axles formed directly into the profileflanges. This type of rail is particularly economical and moreover itcan be produced directly by profiling a sheet metal band, embossed in aprevious stage.

However, this type of rail cannot contain a high density of rollerssince a minimum quantity of matter must be preserved between the rollersso as not to make it brittle.

The present invention offers a rail structure similar to that describedin the previously mentioned document FR-A-2 563 506. It advantageouslyoffers still higher resistance and reduces the production costsignificantly.

SUMMARY OF THE INVENTION

The rail according to the invention consists of the association of alower profile whose section is U-shaped or omega-shaped and of an upperprofile consisting of a steel band, for example, cut and embossed, usedas a roller carrier, which band comprises edges which are folded andcrimped on the rims of the lower profile, which edges are linked bycrossbeams between which the rollers are positioned.

According to one embodiment of the invention, the sheet metal bandmaking up the upper profile comprises axles which are produced by adirect cutting and embossing process and which are associated with theedges. Besides, the length of the crossbeams linking the edges isgreater than the width of the rollers and their width is relativelysmall in order to facilitate folding and tilting the edges practicallyat right angle with respect to the crossbeams, to enable integrating therollers between the axles, whereby the axles can be inserted into thehubs of the rollers and lock the rollers after flattening the edges inthe plane of the crossbeams.

According to another embodiment of the invention, the crossbeams of theupper profile are U-shaped lengthwise in order, to confer to them acertain rigidity and to delineate accurately at their ends, the areawhere the edge is folded with respect to the crossbeam, thereby settinga distance between the folding zones which is vastly greater than thewidth of the rollers. Secondly, this will create and maintain maintainan accurate distance between the lateral walls of the lower profile whencrimping the edges of the upper profile onto the rims of the lowerprofile.

According to another embodiment of the invention, the section of theaxle portions of the rollers looks like an inverted U, which section isinscribed within a circle whose diameter is smaller than that of the hubof the rollers. The height of the axle portions is more or less equal tothe radius of the hub and their useful length is in the same order ofmagnitude as the internal diameter of the hub of the rollers.

According to another embodiment of the invention, the lower portion ofthe lower profile comprises bulges, protruding on either side of thebottom, which bulges improve notably the torsion inertia of the rail andconstitute a kind of multi-purpose slide for clipping or snapping therail on a frame, as well as installing accessories such as, for instancea braking system used as a separator, accommodated inside the profile,between the bottom and the rollers, guided inside the bulges or still byusing the lower profile only, mounting a guiding structure insertedbetween the rails.

The invention also relates to the rail production process. This processconsists in preparing, by folding or profiling operations, from a sheetmetal band, a U-shaped or omega-shaped lower profile and an upperprofile used as a support to the rollers, whereas the assembly isproduced by folding and crimping the edges of the band onto the rims ofthe lower profile.

According to a preferred embodiment of the invention, the processconsists: in preparing in advance the sheet metal band upper profile, bycutting, embossing and forming operations, in order to produce rolleraxles directly and, in installing the rollers while folding the edges atright angle with respect to the crossbeams in order to spread the axlesapart and to enable inserting and integrating the rollers and especiallythe hub of each roller opposite to the axles then: in repositioning theedges flat in the plane of the band and of the crossbeams, which causesthe axles to be inserted into the hub of the rollers, thereby lockingthe rollers.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in detail using the followingdescription and the appended drawings given for exemplification purposesand in which:

FIG. 1 represents, in perspective, a rail portion according to theinvention;

FIGS. 2 and 3 show a portion of the edges with a roller axle, inperspective;

FIG. 4 is a cross section of the roller rail, on the one hand at one ofthe roller axles and, on the other, between an axle and a crossbeam;

FIG. 5 represents, seen from above, a portion of the cut sheet metalband which makes up the upper profile, before notably embossing theaxles that are used as a prop for the rollers and the crossbeams;

FIG. 6 represents the sheet metal band of FIG. 5 after embossing theaxles and the crossbeams;

FIG. 7 is a cross section along 7--7 of FIG. 6 at a crossbeam;

FIGS. 8 to 14 illustrate the various manufacture stages of a rail;

FIG. 15 represents a side view of a rail fitted with a snap or clip forfastening onto a frame;

FIG. 16 is a front view of FIG. 15;

FIG. 17 represents a rail top view, as a longitudinal section, fittedwith a roller braking system, represented in inactive position;

FIG. 18 represents the rail of FIG. 17 with the braking system in activeposition on three rollers;

FIG. 19 is a section along line 19--19 of FIG. 18;

FIG. 20 is a top view section showing the lower profile of a rail,fitted with a guiding structure; and

FIG. 21 is a section of FIG. 20.

DETAILED DESCRIPTION OF THE PREFERRED INVENTION

The rail according to the invention, such as represented on FIG. 1,comprises 3 three elements:--a U-shaped or omega-shaped lower profile 1,comprising the substructure beam,--an upper profile 2 resting on theprofile 1 and whose rims or edges 3 are folded and crimped on the rims 4of the profile 1,--rollers 5, regularly spaced, carried by the profile 2and especially by axles 6 that are formed directly and are part of theprofile 2, as a single block as illustrated in FIGS. 2 and 3. These axleportions 6 are integrated into the hub 7 of the rollers 5, which hub hasthe shape of a tube.

The profile 1 is made of a steel sheet band, formed according to afolding or embossing process.

The profile 2 is, in the same way, also prepared out of a steel band,which has been cut and embossed in order to accommodate the variousrollers 5. The edges 3 of this sheet metal band are then folded andprofiled to be assembled with the profile 1 as described below.

FIG. 4 shows a top view of the rail, as a transversal section.

The profile 1 comprises a bottom 8, lateral bulges 9 and, above thesebulges, lateral walls 10 perpendicular to the said bottom 8 and whoseupper part is made of the rims 4; these rims 4 are folded at right anglewith respect to the lateral walls 10 and they extend to the outside.

The profile 2 rests on the profile 1 and especially on the rims 4 andits edges 3 are folded and crimped on the said rims. It can be notedthat the width of the rail at the bulges 9 corresponds more or less tothe width of the rail at the profile 2 and especially of the edges 3.

The profile 2 also comprises the axles 6 that extend to the inside ofthe rail over a useful length, which corresponds more or less to thediameter of the hub 7 of the roller 5.

The roller 5 rests on the upper rounding 11 of the axles 6. It can benoted in FIG. 2 that the axle 6 looks like an inverted U. The section ofthese axles 6 is inscribed within a circle. The diameter of the circlesurrounding this axle is marginally smaller than the diameter of thebore of the hub 7 so that the lower ridges 12 of the axle 6 do not touchthe hub 7 of the roller 5. The height of the axles 6 is even slightlysmaller than the radius of the hub 7.

The axles 6 are embossed and protrude above the upper plane of the edges3.

The rollers 5 are made conventionally of a plastic material such aspolyamide.

As can be seen on the left portion of FIG. 4, a portion of the crossbeam13 extends between both edges 3 of the upper profile 2. This crossbeam13 whose section looks like an inverted U enables calibration of theinternal width L of the lower profile 1, which width is slightly greaterthan the total length of the hub 7 of the rollers 5. This crossbeam 13enables setting the lateral walls 10 when crimping the edges 3 of theupper profile 2 on the borders 4 of the lower profile 1.

FIG. 5 shows the sheet metal band, which constitutes the profile 2,after the cutting operation. This sheet metal band is cut, thus exposingthe edges 3, the crossbeams 13 as well as windows 14 in which therollers 5 are accommodated. The windows 14 have a width D, taken betweenthe edges 3, which is greater than that of the hubs 7 of the rollers 5and especially greater than the width L between the lateral walls 10 ofthe lower profile 1 in order to prevent any friction of the rollers onthe rims of the window.

In the windows 14, starting from the edges 3, the axles 6 are embossedas illustrated in FIG. 6, to obtain the shape illustrated in FIGS. 2 and3.

The edges 3 are then linked together using the crossbeams 13. Thesecrossbeams separate consecutive rollers 5. They consist of a sheet metalband whose length is vastly greater than the width of the rollers 5. Thecrossbeams can extend as far as into the edges 3 through cut-outs 15whose depth ranges between 2 and 4 mm. This arrangement enables foldingthe edges 3 with respect to the crossbeams 13 around a line defined bythe segment 16, which is situated in a zone at the end of the crossbeams13.

FIG. 6 represents the portion of sheet metal band of FIG. 5 afterembossing. This embossing enables forming the axles in causing them toprotrude above the plane of the upper profile 2; it also enables formingthe crossbeams 13 to confer them a certain resistance.

These crossbeams 13 are embossed longitudinally to form a U-shaped rigidbeam whose sides 17 extend downwardly as shown in FIG. 7. The height ofthe sides 17 is in the order of a few millimeters, sufficient to be usedas a spacer, as represented in FIG. 4, for the lateral walls 10 of thelower profile 1.

The zone 18 situated at each end of the crossbeams 13 corresponds to thefolding area mentioned previously and which will be detailed inconnection with FIGS. 10 to 12.

It is in this zone 18 that the folding line 16 is situated and it is thepresence of this zone that facilitates folding the edges 3 with respectto the crossbeams 13. The crossbeams 13, strengthened by their U-shapedsection, rest indeed perfectly rectilinear.

FIG. 8 represents the lower profile 1 on its own, in reverted positionsuch as shown after forming with a view to integration into the assemblyline of the rail as represented in FIGS. 9 to 14.

The bottom 8, whose width is greater than the space L, is locatedbetween the lateral walls 10 in order to form the bulges 9. The sectionof these bulges 9 is more or less square and they protrude with respectto the lateral walls 10.

The rims 4 are on a plane parallel to that of the bottom 8. They areperpendicular to the lateral walls 10 and extend to the outside from thewalls.

The sheet metal band that constitutes the profile 2 is represented as afront view and turned upside down in FIG. 9. The U-shaped axles 6 areoriented with their aperture turned upwardly. The crossbeam 13, alsoexhibiting a U-shape, is open upwardly.

FIG. 10 shows the folding of the band forming the profile and especiallythe tilting of the edges 3, around the folding lines 16, i.e. at theareas 18 that are situated at the ends of the crossbeams 13. Thisfolding enables spreading the axles 6 apart in order to insert betweenthe axles as shown in FIG. 11, the rollers 5 while having their hub 7opposite to the said axles. As shown in FIG. 12, the sheet metal bandand especially the edges 3 are then flattened, repositioned on the planeof the crossbeams 13 which causes the rollers 5 to be locked by placingand aligning the axles 6 in the hub 7.

Assembling the profile 2 onto the profile 1 to build the roller railconsists first of all in folding the ends of the edges 3 at right angle.The pleats 19 thus provided and the ends of the sides 17 of thecrossbeams 13 form a recess in which the rims 4 of the profile 1 can beintegrated.

These rims 4 rest on the internal section of the edges 3. Then, as shownin FIG. 14, the pleats 19 of the edges 3 are closed on the rims 4 andcrimped or stapled; this provides a high inertia, particularlyheavy-duty rail.

FIGS. 15 and 16 show the installation of a rail on the crossbeam 20 of aframe. This installation resorts to clips 21, for instance, which enablesnapping the rail on the crossbeams 20. These clips, made of plastic orother material, are of a shape complementary to that of the lowersection of the profile 1. The lateral bulges 9 located at the lowersection of the profile 12 build up a kind of slide on which the clips 21are snapped.

These clips 21 comprise an elastic tongue 22, for example fitted with atleast one snug 23, which snug co-operates with an appropriate orificeprovided in the crossbeam 20.

FIGS. 17 to 19 show a particular assembly for this kind of rail whichenables locking three rollers while causing them to protrude in order toconstitute a partition.

This system comprises two elements:--a pull cord 30 resting on thebottom 8 of the profile 1 and a block 31 of appropriate material such asrubber, with the shape of a rectangular plate guided inside the profile1 and especially in the lateral bulges 9. This plate 31 contains acenter groove to cover the pull cord 30 and the snugs 32 that connectthe plate to the pull cord 30.

These snugs 32 are placed under the pads 33 for example the pads extendabove the plate 31 and have a shape appropriate to co-operate with therollers 5. Each of these pads 33, represented as three in number thefigure, corresponds to a roller 5 and, in the active position, as seenrepresented in FIG. 18, they are situated below the rollers 5, whichrollers are more or less elevated with respect to the rollers 5 whichhave remained free, raised by a distance E, approx. 2 mm for instance.

This distance enables the braked rollers to protrude with respect to theother rollers of the rail and of the belt. These few braked rollers aresufficient to slow down packages or parcels circulating on the belt in adynamic store, for example.

FIGS. 20 and 21 show the lower profile 1 only, to which a guidingstructure or partition is connected, liable to be inserted into a beltof complete rails, either between two rails or even along a belt. Thisstructure consists for instance of a flat 35, folded suitably to form aguide using its branch 36 protruding above the profile 1 between theends 37 and 39.

The ends 37 and 39 of the guide, perpendicular to the branch 36,comprise pleats 40 and 41 respectively, at right angle, resting on thebottom 8 of the profile 1. These pleats are locked using wedges 42engaging into the bulges 9 of the profile 1 and extending between thelateral walls 10.

The width of the flat 35 and its pleats 40 and 41 is vastly smaller thanthe distance L separating the lateral walls 10 from the profile 1. Thepleats are accommodated and locked in a groove 43 provided in the centreportion of the wedges 42.

These wedges 42 are integral with the pleats 40 and 41 via a snug 44arranged at the centre and protruding downwards in the groove 43; thissnug is located in an orifice 45 provided in the pleats 40 and 41.

These guiding structures are inserted into a profile 1, which profile isfixed on the frame like the other roller rails, using snaps or clips 21.

The form of these guiding structures is moreover readily adjustable tothe restraints imposed by the belts of roller rails, since it sufficesto fold to the flat 35 according to the requirements in order toconstitute, as represented as a thin dotted line, a protrusion 46 forinstance to serve as a guide at the inlet section of a belt.

What is claimed is:
 1. A roller rail comprising:a lower profile whosesection is one of, U-shaped or omega-shaped; a plurality of rollers; andan upper profile made of a steel band, cut and embossed, used as aroller carrier, which band comprises edges which are folded and crimpedon upper rims of said lower profile, which edges are linked together bycrossbeams between which said rollers are positioned.
 2. The roller railaccording to claim 1, wherein the upper profile comprises axles whichare produced by a direct cutting and embossing process of the steelband.
 3. The roller rail according to claim 2, wherein the crossbeamshave a given length and the rollers have edges and a given width, andwherein the length of the crossbeams is slightly greater than the widthof the rollers between the edges and in that their width at the edges isrelatively small in order to facilitate tilting the edges with respectto the ends of said crossbeams due to a folding operation, atapproximately a right angle, to enable integrating said rollers betweenthe axles, whereby said axles can be inserted into a hub of said rollersby flattening the edges in the plane of said crossbeams.
 4. The rollerrail according to claim 3, wherein the crossbeams comprise U-shapedbeams, which beams serve as spacers between lateral walls of the lowerprofile to accurately locate the folding zones of the edges at the endof the said crossbeams.
 5. The roller rail according to claim 3, whereina section of the axles is of inverted U-shape, which section isinscribed within a circle whose diameter is smaller than that of the hubof the rollers, the height of said section being slightly smaller thanthe radius of said hub and its length being of the same order ofmagnitude as the internal diameter of the hub of said rollers.
 6. Theroller rail according to claim 1, wherein the lower profile comprises:alower section; a bottom; and bulges protruding on either side of thebottom to form a multi-purpose slide.
 7. The roller rail according toclaim 6, further comprising:clips; a flexible tongue on said clips; asnug on said tongue; a frame; a crossbeam on said frame; an orifice insaid crossbeam; said bulges, in co-operation with the clips fitted withsaid flexible tongue fastening said rail on the crossbeam of the framewhile locking said snug of the tongue in the orifice of said crossbeam.8. The roller rail according to claim 6, further comprising inside thelower profile:a roller braking system comprising a pull cord resting onthe bottom of said lower profile; and a block comprising a plate guidedin the bulges of said lower profile, said plate being connected to saidpull cord and containing pads which co-operate by moving the pull cordwith an underside of said rollers in order to stop them and thus to forma separating device.
 9. The roller rail according to claim 6, furthercomprising a guiding structure in the form of a flat fastened only tosaid lower profile by wedges inserted in the bulges of said lowerprofile.
 10. The roller rail according to claim 1, wherein said lowerprofile comprises:a bottom; and lateral walls whose upper portioncomprise rims folded at a substantially right angle towards theexterior.
 11. The roller rail according to claim 1, wherein the upperprofile serves as a carrier for a plurality of rollers and has axlesintegrated into a hub of the rollers.
 12. The roller rail according toclaim 1, further comprising:a bottom on said lower profile; lateralwalls on said lower profile, whose upper portion comprise rims folded ata substantially right angle towards the exterior; and the upper profileserving as a carrier for a plurality of rollers and having axlesintegrated into a hub of the rollers.
 13. A process of manufacture of aroller rail comprising:preparing by, one of, folding or profilingoperations, a sheet metal band, a lower profile with one of, U-shaped oromega-shaped section, and an upper profile carrying a plurality ofrollers; and assembling said profiles together by folding and crimpingthe edges of the sheet metal band constituting said upper profile ontoupper rims of said lower profile.
 14. The process according to claim 13,further comprising, prior to assembling the lower and upperprofiles:preparing said upper profile, by cutting, embossing and formingoperations, in order to provide axles directly on the rollers; andmounting said rollers while folding edges thereon with respect tocrossbeams in order to spread axles apart and enable integration of therollers between the axles, which axles then engage into hubs of therollers when flattening the edges, in the plane of said crossbeams,thereby locking the rollers.